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Biomedical subjects

L Fuller

Publications and source records attributed to L Fuller.

At least 19 recordsLinked to original sources
PubMed2006

Histomonas meleagridis in chickens: attempted transmission in the absence of vectors.

The progress and transmission of blackhead disease in chickens was studied in battery cages and floor pens in the absence of vectors. Two-week-old chicks were inoculated intracloacally with Histomonas meleagridis and allowed to commingle with others in floor pens. There was no confirmed transmission of blackhead to other birds in the pen, whether stocked at 10% or 25% with infected birds. A second experiment evaluated the effects of feed restriction of chickens on spread of blackhead within floor pens. Inoculated seeder birds had severe cecal lesions of blackhead at necropsy, regardless of feed restriction. Uninoculated birds did not develop lesions by the time of necropsy at 42 days of age, regardless of whether full-fed or limited by skip-day feeding. Chickens inoculated intracloacally with H. meleagridis and placed in battery cages became infected and had cecal lesions of blackhead, but few liver lesions. Chickens allowed to commingle with the inoculated birds in batteries had no lesions of histomoniasis at necropsy 2 wk postinoculation. Coccidial oocysts from turkeys (Eimeria adenoeides) were inoculated along with H. meleagridis from cultures to test the effects of sporozoite penetration in the ceca on progress of blackhead disease. Histomoniasis was not worsened by the interaction with sporozoites, as shown by unchanged severity of cecal lesions, the number of birds showing liver lesions, or the overall number of positive birds. Overall, blackhead infections showed no inclination to spread from bird to bird under conditions of these studies, in contrast to what has been reported for turkeys. These results suggest that the dynamics of blackhead transmission in chickens differs significantly from that of turkeys, where transmission from bird to bird is rapid and effective in the absence of vectors.

Animal Feed↗
PubMed2005

Blackhead disease in turkeys: direct transmission of Histomonas meleagridis from bird to bird in a laboratory model.

The spread of Histomonas meleagridis infections through groups of turkeys in the absence of the cecal worm vector (Heterakis gallinarum) was studied in a battery cage model. Battery-reared poults were exposed at 2 wk of age by commingling with infected birds into cages that had the floor lined with paper. One treatment received no exposure, whereas other birds were commingled with two, three, or four birds/cage (25%, 37.5%, or 50%) inoculated per cloaca with cultured H. meleagridis (200,000/bird). Inoculated birds died at 7-13 days postinoculation (DPI) showing typical liver and cecal lesions of histomoniasis. By 14 DPI, 87.5% of the directly inoculated birds died or had severe lesions of histomoniasis. Turkeys commingled with two, three, or four infected birds became infected at the rate of 72%, 80%, or 75%, respectively. In another experiment, two birds/cage (25%) were inoculated with Histomonas from culture and allowed to commingle with other birds for 1, 2, 3, or 4 days. Two of 12 (16.7%) birds had minor cecal lesions after contact with inoculated birds for 1 day, but 87.5%-100% became infected if inoculated birds remained in the cage for 2-4 days. Contemporaneous inoculation with cecal coccidia (Eimeria adenoeides) as a predisposing factor in blackhead infections was studied using the model. Turkey poults directly inoculated with Histomonas were allowed to commingle for 5 days with uninoculated birds that had received inoculation with 0, 10(3), or 10(4) sporulated oocysts. The coccidian infection appeared to interfere with transmission of blackhead infection by 7 DPI, as suggested by lessened severity of cecal lesions and a lower percentage of infected birds. These studies confirm that histomoniasis is transmitted readily from directly exposed young turkeys to others in the absence of the cecal worm vector, and that this phenomenon can be reproduced in battery cages as an experimental model.

Animals↗
PubMed2004

Infection of turkeys with Histomonas meleagridis by the cloacal drop method.

The infection of turkeys with Histomonas meleagridis was attempted in the absence of its normal vector Heterakis gallinarum, using several experimental techniques. Battery-reared poults were inoculated at 2 wk of age with histomonads cultured in vitro, by several routes, including (a) per os (PO), (b) intradoacal (CI), and (c) cloacal drop (CD). Feed restriction was also studied as a predisposing factor. Intracloacal inoculation (CI) consistently produced severe infections in all experiments. In several experiments, turkeys did not become infected after inoculation PO with 1 x 10(5) cultured histomonads. Feed restriction prior to inoculation did not make turkeys susceptible to infection inoculated PO. However, when liquid cultures containing histomonads were applied to the vent (CD) and the dorsal lip stimulated to initiate cloacal drinking, the histomonads were taken into the cloaca and transported to the ceca by retrograde peristalsis. Heavy infections were produced by this method, with severe liver and cecal lesions recorded when birds were necropsied 12 days later. These results suggest that CD may provide ready entry into the lower intestinal tract for these parasites and may facilitate spread of infection through flocks.

Animals↗
PubMed2001

Six-year clinical effect of donor bone marrow infusions in renal transplant patients.

BACKGROUND: To date, several single- and multicenter clinical trials have attempted to induce specific immunological unresponsiveness using donor bone marrow cell infusions to augment solid organ transplantation, but the outcomes have not been definitive. METHODS: Between September 1994 and May 1998, 63 cadaver (CAD) renal transplant recipients of either one or two postoperative donor bone marrow cell (DBMC) infusions were prospectively compared with 219 non-infused controls given equivalent immunosuppression. There was at least a 1 HLA DR antigen match present between donors and recipients. The immunosuppressive regimen included a 10-day course of OKT3 induction, and tacrolimus, mycophenolate mofetil, and methylprednisolone maintenance. A total 7.01x10(8)+/-1.9x10(8) (SD) DBMC/kg was infused into the CAD recipients on either days 4 and 11 (n=42) or one half of that dose on day 4 (n=21) postoperatively. Clinical follow-up has ranged from 2.9 to 6.3 years (mean, 4.7 years). Studies were also performed of humoral immunity and quantitative cellular chimerism. RESULTS: There is clear-cut equivalence in immunosuppressive dosaging and in the other major demographic variables in both groups. However, only 2/63 DBMC recipients had biopsy-proven chronic rejection, whereas 41/219 showed chronic rejection in the controls (P = <0.01). In both groups, mortality was not associated with rejection. The actuarial graft survival at 6.3 years in the CAD DBMC group was 84.3% compared with 72.2% in the control group (not statistically significant). However, if death with a functioning graft was excluded, graft survival was 94.1% in the DBMC group and 79.8% in the controls (P=0.039). Forty patients in the control group continue to have deteriorating renal function (increasing serum creatinine concentrations to 2 mg/dl and higher), compared with 2 patients in the DBMC group (P=0.04). In the DBMC group, chimerism in iliac crest marrow aspirates has increased 3-fold in yearly sequential measurements between 1 and 4 years postoperatively averaging 1.3+/-0.36% (SE) most recently. This has not occurred in the controls. CONCLUSIONS: There now appears to be more solid long-term evidence, in kidney transplant recipients prospectively receiving DBMC infusions, of an improvement in long-term graft survival, and of the degree of chimerism positively correlating with the absence of graft loss.

Adolescent↗
PubMed2001

Effects of zafirlukast upon clinical, physiologic, and inflammatory responses to natural cat allergen exposure.

BACKGROUND: Leukotriene receptor antagonists have been shown to attenuate physiologic changes in the upper and lower airways induced by allergen challenge. However, it is unknown whether these drugs modulate airway inflammation after exposure to allergen in a natural setting. OBJECTIVE: To determine the effects of the oral leukotriene receptor antagonist zafirlukast upon symptoms, changes in pulmonary function, and indices of inflammation in the upper and lower airways induced by natural exposure to cats. METHODS: Zafirlukast, 20 mg twice daily, or placebo was administered to 18 cat-allergic asthmatic patients in this randomized, double-blind, crossover study. Cat room challenges were performed after a 1-week period of each treatment. Upper and lower airway symptoms were measured and spirometry performed before and at regular intervals during each challenge. Nasal lavage and sputum induction were performed 24 hours before and after each challenge. RESULTS: Zafirlukast significantly improved the prechallenge baseline FEV1 (P = 0.001) and attenuated the decrease in FEV1 induced by cat challenge (P = 0.019). Zafirlukast also significantly reduced lower airway symptoms associated with cat challenge (P = 0.005) but had no effects on nasal symptoms. Although zafirlukast did not significantly differ from placebo in its effects on sputum inflammatory cells or eosinophil cationic protein, it significantly reduced the absolute counts of total white cells, lymphocytes, neutrophils, and basophils in nasal lavage fluid. CONCLUSIONS: Zafirlukast, 20 mg twice daily for 1 week, demonstrated a significant protective effect on symptoms of asthma and alterations in pulmonary function induced by natural cat exposure, whereas nasal symptoms and markers of sputum inflammation were not affected by the medication.

Administration, Oral↗
PubMed2000

Donor bone marrow-derived chimeric cells present in renal transplant recipients infused with donor marrow. I. Potent regulators of recipient antidonor immune responses.

BACKGROUND: Even though a number of transplant centers have adopted donor-specific bone marrow cell (DBMC) infusions to enhance donor cell chimerism, to date there has been no direct evidence linking chimerism with tolerance induction in human organ transplant recipients. METHODS: Cells of donor phenotype were isolated 1 year postoperatively from the peripheral blood lymphocytes and iliac crest bone marrow of 11 living-related-donor (LRD) renal transplant recipients, who had received perioperative donor bone marrow cell infusions. These recipient-derived donor (RdD) cells were characterized phenotypically by flow cytometric analysis and functionally as modulators in mixed lymphocyte reaction (MLR) and cell-mediated lympholysis (CML) assays. RESULTS: The yield of RdD cells ranged from 0.1 to O.9% of the starting material with the majority being TcRalphabeta, CD3 positive T cells, a substantial percentage of which coexpressed CD28. At 1 year posttransplant almost 50% of the LRD-kidney/DBMC recipients tested so far exhibited donor-specific unresponsiveness in MLR (7/17) and CML (6/13) reactions and this trend was further enhanced at 23 years. In the recipients with residual positive antidonor immune responses, the RdD cells inhibited recipient antidonor MLR and CML responses significantly more strongly than freshly isolated and similarly treated iliac crest bone marrow cells from the donor. RdD cells also inhibited the MLR of the recipient to third party allogeneic stimulator cells; however, this nonspecific effect was significantly weaker than specific inhibition. We also established long-term bone marrow cultures stimulated every 2 weeks with irradiated alogeneic feeder cells, that had similar functional properties thus possibly providing us with an in vitro correlate the RdD cells. CONCLUSIONS: These results clearly support the notion that the infused donor cells play a positive role in the induction and/or maintenance of transplant tolerance.

Bone Marrow Transplantation↗
PubMed2000

Involvement of multiple subpopulations of human bone marrow cells in the regulation of allogeneic cellular immune responses.

BACKGROUND: The identity of the cells in the human bone marrow that function as effective regulators of in vitro and possibly in vivo cellular immune responses is not well established. METHODS: Cell subpopulations were isolated from cadaver donor vertebral-body bone marrow cells (DBMC) by using immuno-magnetic microbeads and were tested as inhibitors (modulators) in cell-mediated lympholysis (CML) and mixed lymphocyte reaction (MLR) responses of normal peripheral blood lymphocytes stimulated with irradiated cadaver donor spleen cells. RESULTS: Compared with spleen cells as controls, un-irradiated T-cell depleted DBMC inhibited both the MLR and CML responses of allogeneic responder cells in a dose dependent manner (as in our previous reports). The inhibition was also mediated by a number of purified subpopulations including pluripotent CD34+ stem cells, and their CD34 negative early progeny of both lymphoid and myeloid lineages. These included DBMC enriched for non-T-cell lymphoid precursors (NT-LP/DBMC; i.e., DBMC depleted of CD3, CD15, and glycophorin-A positive cells) and DBMC positively selected for CD38+, CD2+, CD5+, and CD1+ lymphoid cells (all were depleted of CD3+ cells) as well as CD33+ (but CD15 negative) myeloid precursors. However, positively selected CD19+ B-cells and CD15+ myeloid cells did not inhibit the MLR and CML responses. The NT-LP/DBMC that had been repeatedly stimulated with irradiated allogeneic peripheral blood lymphocytes caused the strongest inhibition of the MLR and CML responses of the same allogeneic cells with 200 times fewer modulator cells needed than uncultured DBMC (P<0.001). Flow cytometric analysis revealed that majority of cells in these cell lines had become CD3+ TcR-alphabeta+ CD4+ and CD28+ cells. CONCLUSION: A variety of less differentiated cells of various lineages residing in the human bone marrow are immunoregulatory in vitro. Among them, there is at least one subset that can undergo differentiation in vitro into regulatory T cells that can be maintained in long-term cultures.

Antigens, CD34↗
PubMed2000

Vaginal misoprostol administered 1, 2, or 3 days after mifepristone for early medical abortion: A randomized trial.

CONTEXT: The conventional timing of misoprostol administration after mifepristone for medical abortion is 2 days, but more flexible intervals, which may make the regimen more convenient, have not been studied. OBJECTIVE: To determine whether vaginal misoprostol administered 1, 2, or 3 days after mifepristone influences safety or effectiveness for abortion at up to 56 days' gestation. DESIGN: Prospective, randomized, open-label trial conducted from March 1998 to June 1999. SETTING: Sixteen US primary care and referral abortion facilities. PATIENTS: A total of 2295 healthy patients aged 18 years or older who were 56 or fewer days pregnant. Forty (1.7%) were lost to follow-up. INTERVENTIONS: Patients received 200 mg of oral mifepristone and were randomly assigned to self-administer 800 microg of vaginal misoprostol at home 1 (n = 745), 2 (n = 778), or 3 (n = 772) days later. Women returned to the clinic up to 8 days after mifepristone for ultrasonographic evaluation. A second dose of misoprostol was administered if the abortion was not complete. Patients with continuing pregnancy, excessive bleeding, or retained pregnancy tissue 5 weeks later received an aspiration curettage. MAIN OUTCOME MEASURES: Effectiveness of the procedure (ie, a complete medical abortion without surgical intervention), adverse effects, acceptability of the procedure based on patient questionnaires, reasons for surgical intervention, and adverse outcomes, compared among the study groups. RESULTS: Of the 2255 women completing follow-up, complete medical abortion rates were 98% (95% confidence interval [CI], 97%-99%) among those using misoprostol after 1 day, 98% (95% CI, 97%-99%) for those using misoprostol after 2 days, and 96% (95% CI, 95%-97%) among those using misoprostol after 3 days. Fifty-five subjects aborted before taking misoprostol, 9 had early surgery, and 103 did not take misoprostol on their assigned day. No blood transfusions were required. Cramping and nausea were the most common adverse effects reported, with similar percentages of patients in all 3 groups reporting such effects. Thirteen unexpected or serious adverse events occurred: 6 in those using misoprostol after 1 day; 4 in those using it after 2 days; and 3 in those using it after 3 days. Nearly all women (>90%) found the procedure to be acceptable. CONCLUSIONS: Our results suggest that vaginal misoprostol, 800 microg, can be used from 1 to 3 days after mifepristone, 200 mg, for early medical abortion, and need not be administered strictly 48 hours after mifepristone. JAMA. 2000;284:1948-1953.

Abortifacient Agents↗
PubMed2000

Low-dose mifepristone followed by vaginal misoprostol at 48 hours for abortion up to 63 days.

The aim of this study was to compare the effectiveness, side effects, and acceptability of one-third the standard dose of mifepristone, i.e., 200 mg, and vaginal misoprostol 800 microg to induce abortion in subjects < or =56 days pregnant with subjects 57-63 days pregnant. A prospective multicenter trial enrolled healthy women > or =18 years, < or =63 days pregnant, and wanting an abortion. Women received mifepristone 200 mg orally, followed by misoprostol 800 microg vaginally, and returned 1-4 days later for ultrasound evaluation. A second dose of misoprostol was administered, if necessary. Surgical intervention was indicated for continuing pregnancy, excessive bleeding, or persistent products of conception 5 weeks later. Of 1137 subjects, 829 were in the < or =56 days pregnant group and 308 in the 57-63 days pregnant group. In all, 34 subjects had surgical intervention and 16 were lost to follow-up. Complete medical abortions occurred in 97% of subjects < or =56 days pregnant and 96% in the 57-63 days pregnant group. In all, 88% of subjects in the < or =56 days pregnant and 92% in the 57-63 days pregnant group bled within 4 h of using vaginal misoprostol. Comparing subjects < or =56 days pregnant with 57-63 days pregnant, there was less diarrhea (20% vs 29%, p = 0.002) and vomiting (33% vs 44%, p = 0.001), although side effects were acceptable to 82% of subjects in both groups. One subject in the < or =56 day group required a transfusion for delayed excessive bleeding. Although bleeding (p = 0.01) and pain (p = 0.02) were less acceptable in the 57-63 day group, 91% of subjects in both groups reported that the overall procedure was acceptable. In summary, low-dose mifepristone 200 mg and home administration of vaginal misoprostol 800 microg at 48 h were highly effective and acceptable to women < or =63 days pregnant, thereby expanding the number of women who can access a medical abortion.

Abortifacient Agents↗
PubMed2000

Bone marrow cells inhibit the generation of autologous EBV-specific CTL.

Recently, we reported that human bone marrow cells (BMC) inhibited the proliferative (recall) response of lymphocytes to Epstein-Barr virus (EBV) and cytomegalovirus (CMV) protein antigens [12]. To clarify further the effect of BMC on the immune response to viral antigens, we obtained PBL from EBV IgG antibody positive kidney transplant recipients (R) and their living-related donors (LRD) 1 year after renal transplantation and generated EBV-specific CTL in vitro in the presence or absence of autologous BMC. The addition of freshly aspirated autologous iliac crest BMC from either R or LRD caused a significant inhibitory effect on the generation of EBV-specific CTL from CTL precursors, in contrast to the addition of autologous PBL used as controls (62.29 +/- 10.85% inhibition using BMC from the kidney transplant recipients; 74.47 +/- 15.21% inhibition using BMC from the living-related donors). This inhibitory effect was only exerted during the CTL generation phase; but not in the effector CTL killing phase. The expression of CD94, a component of the killer inhibitory receptor (KIR) on CD3(+) cells was elevated in the cultures with BMC, in contrast to the cultures without BMC. The BMC inhibitory effect was partially abrogated by pre-incubation of the CTL effectors with anti-CD94 monoclonal antibody, in contrast with its isotype control. In addition, supernatants obtained from the CTL generating cultures with BMC contained high levels of prostaglandin E(2) (PGE(2)), and EBV-specific CTL activity was inhibited by the addition of exogenous PGE(2) in the absence of BMC. The induction of CD40L cell surface expression by anti-CD3 was also decreased on the effector T cell population when BMC were added. There was a concomitant reduction in protein kinase C (PKC) activity. These studies demonstrate that BMC exert an inhibitory effect on T cell-mediated immunity to viral antigens in humans by regulating autologous effector T cell generation and early T cell activation signaling pathways.

Antigens, CD↗
PubMed2000

Bone marrow cells promote TH2 polarization and inhibit virus-specific CTL generation.

This laboratory recently reported that human bone marrow cells (BMC) inhibit the generation of virus-specific CTL in culture. The culture supernatants contained increased levels of prostaglandin E(2) (PGE(2)) (shown to favor TH2 cell development) and also inhibited EBV-CTL effector cell development. In this study, we obtained PBL from Epstein-Barr virus (EBV) IgG antibody positive kidney transplant recipients (R) and their living-related donors (LRD) one year after renal transplantation. EBV-specific CTL were then generated in vitro by stimulating PBL with autologous EBV-transformed B cells (EBV-B) in the presence or absence of autologous BMC. The addition of BMC to the EBV-CTL generation cultures increased the intracellular expression in CD3+ cells of IL-4,-5,-6,-10, and -13. These CD3+ cells also expressed increased levels of the TH2 associated receptor CCR3. Inhibition was even observed by preparing EBV-CTL generating cultures in trans-wells that separated the autologous BMC from the PBL + EBV-B. It was then observed that CD3+ cells obtained after 7 days of culture in the presence of autologous BMC could be used as inhibitors of EBV-CTL generation. Protein Kinase A (PKA), a cAMP kinase that is involved in the upregulation of TH2 cytokine activity, was increased in EBV-CTL cultures by the presence of BMC. Additionally, IL-4-mediated signal transduction and activation of transcription (STAT-6) phosphorylation was slightly increased. These results show that the BMC inhibition is mediated by soluble factors (cytokines) and that cell-cell contact in this autologous system is not required, so that BMC (at least partially, via cytokine production) promote TH2 polarization in culture. Moreover, TH2 cells induced by culturing with autologous BMC directly inhibit EBV-CTL generation, and TH2 associated PKA, CCR3, and STAT-6 phosphorylation are enhanced by BMC.

Bone Marrow Cells↗
PubMed2000

Radiographic appearance of the chest following therapy for Hodgkin disease.

This study was carried out to define the post-treatment appearance of the chest radiographs in 44 consecutive patients with Hodgkin disease who received mantle irradiation with or without chemotherapy and to determine how the incidence and severity of post-treatment abnormalities relate to the radiation parameters and chemotherapeutic regimens. Radiographs of the chest in 44 patients, computed tomograms of the chest in 31 patients and of the abdomen of 35 patients were reviewed, prior to and following treatment, for mediastinal contours, pericardial status, cardiac size and pulmonary fibrosis. All patients were followed for a minimum of 1 year and 27 were followed for more than 5 years. Stable post-treatment imaging studies were correlated with the initial extent of disease, radiation parameters, and chemotherapeutic regimens. Stable post-treatment findings were categorised as follows: the chest radiograph was normal or showed subtle vascular reorientation; moderate paramediastinal fibrosis was present; severe pulmonary fibrosis had occurred with narrowing of the cardiomediastinal silhouette in some patients. In general, the severity of the fibrosis was dependent on (1) the size of the radiation fields and on whether or not the coverage of the hila included a 1- to 2-cm margin; (2) the amounts of chemotherapy and particularly bleomycin containing regimens and (3) individual susceptibility of normal tissue irradiation. Therapy for Hodgkin disease is not necessarily associated with radiographic sequelae regardless of the initial status of the mediastinum or the treatment. However, the post-treatment appearance of the chest radiographs in this study was related strongly to (1) the initial extent of disease and particularly the status of the hila, both of which influenced the amounts of lung parenchyma that were included in the treatment fields; (2) the use of bleomycin in chemotherapy regimens and (3) individual normal tissue radiosensitivity.

Adolescent↗
PubMed2000

Use of higher dose extended interval aminoglycosides in a neonatal intensive care unit.

The objective of this study is to determine the safety and efficacy of an extended interval aminoglycoside dosing guideline implemented in our neonatal intensive care unit (NICU). A retrospective review of pharmacokinetic data on 44 patients led to the development of an extended interval aminoglycoside guideline utilizing a 5-mg/kg dose given at an interval based on postconceptional age and risk factors that may alter aminoglycoside clearance. After implementation of the new clinical guideline, a retrospective review of patient records was performed. Thirty-six of 43 peak levels were within the goal range. Trough levels were <1 microg/mL in 41 of 46 patients, with no trough >2 microg/mL. Thirty-three patients had clinical or culture proven sepsis and were successfully treated with the new regimen. No difference between pre- and post-treatment blood urea nitrogen (BUN) and serum creatinine values was observed. Hearing evaluations were performed in 32 patients with one failure. The patient who failed the hearing screen, passed a follow-up hearing test. Three deaths, none attributed to infection or the drug, occurred during the evaluation period. The dosing guidelines developed for our NICU patients are safe and effective, although evaluation of the longterm potential for ototoxicity should be performed.

Anti-Bacterial Agents↗
PubMed1999

In vitro immunogenicity of cadaver donor bone marrow cells used for the induction of allograft acceptance in clinical transplantation.

BACKGROUND: The cascade of immunological effects brought about by donor bone marrow cell (DBMC) infusions to induce allograft acceptance in clinical transplantation is not fully understood. Aside from acting as immune responding and regulatory cells, the infused DBMC also may sensitize the recipient to the donor antigens. METHODS: To analyze this stimulatory activity of DBMC, in vitro mixed lymphocyte cultures (MLC) and cell-mediated lymphocytotoxicity (CML) culture systems analogous to the transplant model with DBMC infusion were used. RESULTS: When responding peripheral blood lymphocytes (PBL) from normal volunteers were placed in culture with suspensions of Ficoll-purified, T cell-depleted, un-irradiated allogeneic DBMC (NT-DBMC), a reaction was seen in both MLC and CML. However, when compared to allogeneic spleen cells as stimulating cells, the responses to NT-DBMC were of markedly lower magnitude and were not seen when the NT-DBMC was irradiated (3000 R). When responding PBL were stimulated with either NT-DBMC that had been previously cultured with irradiated cells from the responders for 1 week (activated NT-DBMC), NT-DBMC further depleted of CD15+ and glycophorin A-positive cells (NT-LP/DBMC), or purified CD34+ and CD2+ DBMC subsets, stronger lymphoproliferative and cytotoxic responses were observed. Moreover, these responses were not abrogated by irradiation of the stimulating DBMC subpopulations. Depletion of antigen-presenting cells by positive selection of CD3+ cells from the responding PBL abrogated MLC and CML reactivity, even when purified NT-LP/DBMC, the most stimulatory cells, were used. This latter observation was in contrast to the responses seen with cultures containing allogeneic stimulating spleen cell populations. This indicated the requirement for indirect alloantigen presentation, i.e., the failure of these DBMC to stimulate by direct alloantigen presentation. NT-DBMC was able to stimulate responding PBL in secondary MLC and CML responses with an equivalent magnitude, irrespective of whether the stimulators were spleen cells or NT-DBMC. Finally, the MLC and CML responses were inhibited by tacrolimus (FK506), mycophenolic acid (MPA), and cyclosporine (CsA) in a dose dependent manner, in contrast to previously observed refractoriness of DBMC preparations to these agents if DBMC was tested as responder cells or in modulatory assays. CONCLUSIONS: These results indicate that DBMC are able to function as effective in vitro stimulators, but only by indirect antigen presentation, and that the immune responses mediated by them can be down-regulated by their own inherent suppressive nature, an effect that can be enhanced by the presence of immunosuppressive drugs.

Antibody Formation↗
PubMed1999

Effects of T'ai Chi on balance.

OBJECTIVE: To determine if the practice of T'ai Chi significantly improves balance. METHODS: Twenty-two persons with mild balance disorders were studied. Five measures of balance were obtained, including 3 objective measures (moving platform posturography, Romberg testing, and reach testing) and 2 disability questionnaires (Dizziness Handicap Inventory and a modified Medical Outcomes Study general health survey). To be included, patients were required to be able to stand in the eyes-closed regular Romberg position for 30 seconds. The subjects underwent 8 weeks of T'ai Chi training and practice and then were retested. RESULTS: Highly significant improvements were found on both the posturography test and the Dizziness Handicap Inventory questionnaire scores (P<.001 and P=.004, respectively). Trends toward improvement were also noted in Romberg test results and the Medical Outcomes Study survey (P=.03 for both). Reach was not improved. CONCLUSION: These findings suggest that T'ai Chi training improves balance.

Adult↗
PubMed1999

Abnormal esophageal body function: radiographic-manometric correlation.

Stationary manometry is the gold standard for the evaluation of patients with suspected esophageal motility disorders. Comparison of videoesophagram in the evaluation of esophageal motility disorders with stationary motility has not been objectively studied. Two hundred two patients with foregut symptoms underwent stationary motility and videoesophagram. Radiographic assessment of esophageal motility was done by video recording of five 10-cc swallows of barium. Abnormal esophageal body function was defined by stasis of barium in the middle third of the esophagus on at least four swallows or stasis on at least three swallows in the distal third. Stationary manometry was performed using a five-channel water perfused system. Contraction amplitudes <25 mm Hg in any of the last two channels or the presence of simultaneous or interrupted waves in 10 per cent or more were considered to be abnormal. Sixty-two patients had abnormal manometry. Thirty-four patients also demonstrated abnormal videoesophagrams for an overall sensitivity of 55 per cent. The positive predictive value was 53 per cent; specificity was 79 per cent; and negative predictive value was 80 per cent. Sensitivity was greatest in patients with achalasia (94%) and scleroderma (100%) and in patients presenting with dysphagia (89%). Sensitivity was poor for nonspecific esophageal motility disorders. A videoesophagram is relatively insensitive in detecting motility disorders. It seems most useful in the detection of patients with esophageal dysfunction, for which surgical treatment is beneficial, and in those patients presenting with dysphagia.

Adolescent↗